Pieper, Francis. Christian Dogmatics: Volume 2. St. Louis: Concordia Publishing House, 1968.
3 The Personal Union
The human nature of Christ has been assumed into the person of God the Son. This is the personal union - one person despite a divine and a human nature. This is not union only in activity. It is a closer unity than that of Christ and his believers. God the Son is truly God. God is in Christ in such a way that Jesus, the human, is divine. Pieper discusses a number of metaphors often used for the two natures of Christ, showing that none can live up to the genuine unio personalis.
Was Jesus aware of this? In location 1924 Pieper asserts that Jesus knew he was both divine and human. This, however, is not widely accepted. “At all times men, without and within the pale of the Christian Church, have been looking for substitutes for the hypostatic union” (Loc. 1940). Pieper gives examples of attempts to replace this doctrine, all of which fall short of Scripture. His conclusion is that “The salvation of the world could be effected only through the theanthropic work of Christ, and that required a theanthropic Person” (Loc. 1960).
Pieper continues with an analysis of various substitute theories (Loc. 2008 ff).
First, “The union between God and man in Christ is not a nominal union” (2008). The name of God is simply symbolic.
Second, “It is not a union habitualis, relativa, signifying merely a close relationship” (Loc. 2015).
Third, “It is not a unio acidentalis, an external, accidental union” (Loc. 2023).
Fourth, “It is not a union sustentiva, consisting in the mere presence and sustaining power of God” (Loc. 2031).
Fifth, “It is not a unio naturalis. We speak of a natural union in the case of things which have a natural relationship to each other” (Loc. 2035).
Sixth, “It is not a unio essentialis or commixtiva.” (Loc. 2060).
Finally, “The personal union is not a unio per adoptionem” (Loc. 2101).
“The personal Union and the Christological Theories of Modern Theology” (Loc. 2113).
In this chapter Pieper summarizes modern Christological misrepresentations and outlines the motives behind them. Underlying it all, Pieper says, is the rejection of the inerrant and true Word of God, led, in Pieper’s view, by Schleiermacher.
Pieper chooses to speak in this context (Loc. 2136) because implicit in the modern theology is a view of Jesus as merely human. The denial of the two natures of Christ is thus necessary.
In Loc. 2136 Pieper observes that De Wette and Ritschl represent theologians who “do not consider Christ as saving men through His vicarious satisfaction, but through His arousing of moral, pious, intellectual feelings in men” (Loc. 2144).
Pieper also identifies theologians who consider themselves “conservative” and wish to find a “deeper understanding.” These he divides into two categories, kenoticists and advocates of autohypostatic theory.
“The kenoticists seek to obtain this conceivability by reducing the divine nature of the Son of God in His incarnation” (Loc. 2159). Among these Pieper lists Thomasius, Delitzsch, Kahnis, Luthardt, and Zoeckler. This view lowers Christ to the level of having to learn what it is to be human.
“To remove this intellectual difficulty, others have advanced to the autohypostatic theory. They refuse to accept the enhypostasy of the human nature of Christ, that is, its assumption into the Person of the Son of God, and hold that the Man Christ had a personality of His own” (Loc. 2173).
This view separates the personality of human and divine in Christ, some viewing that the natures grow together (Dorner) and some saying they remain distinct (Seeberg, Kirn).
Both views finally deny a Christ who is entirely divine and entirely human. We are left with a Christ who is a mere man, worked upon by God in a unique way. Yet there is none of the union found in Scripture.
Pieper discusses historical terms which are rejected by the modern theologians, such as the terms “person,” “nature,” and the like. As the terms are rejected, so may the person of Christ be rejected. Pieper continues at length detailing the importance and universality of the Lutheran Reformation’s view of the personal union of Christ.